Download Multi-Cell Li-Ion Battery Management System

Application Report
SLAA478 – December 2010
Multi-Cell Li-Ion Battery Management System Using
MSP430F5529 and bq76PL536
Daniel Torres ............................................................................................... MSP430 System Solutions
ABSTRACT
This application report explains the implementation of a multi-cell lithium-ion battery management system
using an MSP430™ microcontroller and the bq76PL536. The battery manager is implemented using the
standard evaluation boards for the MSP430 MCU and the bq76PL536.
The bq76PL536 can be stacked vertically to monitor up to 192 cells without additional isolation
components between ICs. A high-speed serial peripheral interface (SPI) bus operates between each
bq76PL536 and the MSP430 microcontroller to provide reliable communications through a high-voltage
battery cell stack. The battery management system can communicate with an external host or battery
charger using USB communication or asynchronous serial communication such as RS232 or RS485.
This application report demonstrates the following features: passive cell balancing, cell undervoltage
monitor, cell overvoltage monitor, safety cell overvoltage monitor, cell overtemperature monitor. It also
detects whether the battery system is in charge or discharge mode by detecting changes of cell voltages.
Sample application code and other information associated with this application report can be downloaded
from http://www.ti.com/lit/zip/slaa478.
NOTE: This application note is applicable to all the MSP430 devices, the source code provided with
this document can be used as is with the MSP430F5xx family.
Contents
1
Hardware ..................................................................................................................... 2
2
Software ...................................................................................................................... 4
3
References ................................................................................................................. 11
Appendix A
Benefits of the Ultra-Low-Power MSP430-Based Solution ................................................. 12
List of Figures
1
System Block Diagram ..................................................................................................... 2
2
Battery Manager Flowchart ................................................................................................ 5
3
Battery Manager State Machine
4
5
6
..........................................................................................
Cell Charging Profile ........................................................................................................
Battery Pack Threshold Values ...........................................................................................
Cell Balancing Flowchart ...................................................................................................
6
7
7
8
List of Tables
1
Connecting the EVMs ...................................................................................................... 3
2
EVM Power Connections – USB Powered (USB1 Connector on MSP430™ EVM) ............................... 3
3
EVMs Jumper Configuration – USB Powered
4
EVMs Power Connections – 5 V on Power Jack Connector J5 (BQ76PL536) ..................................... 3
5
EVM Jumper Configuration – External Power 5 V on Power Jack Connector J5 (BQ76PL536) ................. 3
6
Asynchronous Serial Port (UART) Connections ........................................................................ 4
..........................................................................
3
MSP430 is a trademark of Texas Instruments.
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
1
Hardware
1
www.ti.com
7
Battery Management System Software Files .......................................................................... 10
8
Supply Currents in Active Mode ......................................................................................... 12
9
Supply Currents in Low-Power Mode ................................................................................... 12
10
Supply Currents in Ultra-Low-Power Mode ............................................................................ 12
Hardware
The battery management system implemented in this application report is based on the existing evaluation
modules for the MSP430F5529 and the bq76PL536. Figure 1 shows the system block diagram. For more
information on these devices, see the device data sheets.[1][2]
The evaluation modules' part numbers are MSP-TS430PN80USB and BQ76PL536EVM-3. These boards
are available from the TI eStore (https://estore.ti.com/). For more details and information related to these
evaluation modules (EVMs), see the specific EVM user's guide.[3][4]
bq76PL536
bq76PL536
RS232/RS485/
USB-CDC Class
SPI-USCIB0
MSP430F5529
Host PC or
Battery Charger
MSP-TS430PN80USB
Target Board
CONV P1.1
bq76PL536
FAULT P1.2
ALERT P1.3
DRDY P1.4
Figure 1. System Block Diagram
1.1
Connecting the Evaluation Modules
The EVMs are connected using standard wire jumpers; Table 1 shows the signal connections between the
two EVMs. By default, the MSP430 MCU and isolation circuitry on the BQ76PL536EVM-3 are powered
using the USB port on the host computer. Table 2 shows the power connections for powering the boards
using the USB VBUS voltage (USB1 connector on the MSP430 EVM). Table 3 shows the jumpers'
configuration when the system is powered using the USB VBUS.
The EVMs can also be powered from an external power supply; Table 4 and Table 5 show this power
configuration.
NOTE: Make sure that the pullup resistors R49, R53, and R60 are removed on the
BQ76PL536EVM-3 board.
2
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
Hardware
www.ti.com
Table 1. Connecting the EVMs
BQ76PL536EVM-3 Connector
Pin Number : Pin Name
Connection Name
MSP-TS430PN80USB Connector
Pin Number : Pin Name
SPI: Select Slave
P5-9 : SPI SS/GPIO
J2-36 : P2.7/USCB0STE
SPI: Slave Input/Master Output
P5-8 : SPI MOSI/GPIO
J2-37 : P3.0/USCB0SIMO
SPI: Slave Output/Master Input
P5-5 : MISO/GPIO
J2-38 : P3.1/USCB0SOMI
SPI: Clock
P5-7 : SCLK/GPIO
J2-39 : P3.2/USCB0CLK
Fault
P4-2 : FAULT
J2-22 : P1.1
Alert
P4-3 : ALERT
J2-23 : P1.2
Data Ready (DRDY)
P4-4 : DRDY
J2-24 : P1.3
Conversion (CONV)
P4-5 : CONV
J2-25 : P1.4
Table 2. EVM Power Connections – USB Powered (USB1 Connector on MSP430™ EVM)
Connection Name
BQ76PL536EVM-3 Connector
Pin Number : Pin Name
MSP-TS430PN80USB Connector
Pin Number : Pin Name
Power : 5 V from USB bus
P5-6 : SPI+5V
J4-65 : VBUS
Power : Ground
P5-2 : GND2
J5-3 : GND
Table 3. EVMs Jumper Configuration – USB Powered
BQ76PL536EVM-3
Jumper : Pin Selection
MSP-TS430PN80USB
Jumper : Pin Selection
JP1 : INT USB
JP1 : 1-2
JP5 : 3.3VDC
JP3 : 2-3
JP4 : 1-2
JP2 : 1-2
JP5 through JP10 : 2-3
Table 4. EVMs Power Connections – 5 V on Power Jack Connector J5 (BQ76PL536)
BQ76PL536EVM-3 Connector
Pin Number : Pin Name
Connection Name
MSP-TS430PN80USB Connector
Pin Number : Pin Name
Power : 3.3 V
JP5 : PIN 2
J5-1 : VCC
Power : Ground
P5-2 : GND2
J5-3 : GND
Table 5. EVM Jumper Configuration – External Power 5 V on Power Jack
Connector J5 (BQ76PL536)
BQ76PL536EVM-3
Jumper : Pin Selection
MSP-TS430PN80USB
Jumper : Pin Selection
JP1 : EXT PWR
JP1 : 1-2
JP5 : 3.3VDC
JP3 : 2-3
JP4 : OPEN
JP2 : 1-2
JP5-10 : 2-3
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
3
Software
1.2
www.ti.com
Communication Ports
The battery management system described in this application report is able to communicate to a host
device over USB or asynchronous serial port (UART). To use the USB communication, it is required to
connect to the host device using a standard male 4-pin USB-A to USB-B cable between the slave and the
master attached to the connector USB1 on the MSP-TS430PN80USB EVM.
It is required to use an external dongle to provide the physical layer for the asynchronous serial port
(UART). The user must build or provide an interface for such purpose. A simple RS232 or RS485 interface
can be used. The RX and TX should be connected as shown in Table 6.
Table 6. Asynchronous Serial Port (UART) Connections
Connection Name
2
MSP-TS430PN80USB Connector
Pin Number : Pin Name
External Physical Layer
Transmit
J2-40 : P3.3/USCA0TXD
TX
Receive
J3-41 : P3.4/USCA0RXD
RX
Software
The battery management system described in this application report is created by configuring, monitoring,
and controlling multiple daisy-chained BQ76PL536 devices. These daisy-chained devices create a battery
pack that could be built up to 192 Li-Ion cells. The demonstration software created for the application
report has the following features:
• Configuring the a multi-stacked battery pack
• Monitoring the multi-cell battery pack voltage and temperature
• Monitoring the individual cell voltage
• Passive cell balancing
• Cell overvoltage and undervoltage protection
• Overtemperature protection
• Charge and discharge mode detection
• Communication to a host device using USB or UART
2.1
Battery Manager
The first task of the battery management software is to initialize the MSP430 MCU peripherals.[5] Then it
builds the battery stack by detecting and configuring the existing BQ76PL536. The next tasks are to
identify the status of the cells and the battery pack by reading the voltages, temperatures, fault, and alert
conditions.
The battery management software is continuously checking for a fail conditions on the battery pack; it
samples the cell voltages and the integrity of the battery pack every second. The system goes to
low-power mode if there are not any corrective actions or pending tasks. A brief description of this process
is shown in Figure 2.
4
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
Software
www.ti.com
MSP430 init,
Communication ports Init,
1-s timer init,
SPI init,
Battery pack init
WAKEUP
Has 1-s timer
expired?
No
Service async
WAKEUP event
Yes
Start voltage
measurement
Sleep
Read each cell data
Check cell status and
battery pack status
Action required?
Yes
Update battery status and
send status to host or
charger signals
No
1-s sleep
Figure 2. Battery Manager Flowchart
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
5
Software
www.ti.com
The battery manager software goes into different states depending on the status of the battery pack.
Figure 3 shows all of the possible states.
COV or POT condition
detected.
Send notification to host.
SOV condition detected.
Send notification to host.
CUV or PUT condition
detected.
Send notification to host.
End of charge
Any cell voltage below
the discharge delta voltage
> charge/discharge time?
Pack voltage reaches the value in
end of charge voltage and the
time in charge taper time has
been exceeded
Discharge mode
Charge mode
Battery pack voltage < full?
Charge clear volts.
Battery stack voltage > full?
Discharge clear volts.
Charge mode
Any cell voltage < charge delta
for more than the
charge/discharge time?
Discharge mode
Pack voltage drops to the value
in end of discharge voltage for
more than the time in
end of discharge qual time
End of discharge
Figure 3. Battery Manager State Machine
6
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
Software
www.ti.com
2.1.1
Protection and Safety Conditions
The battery manager software protects the battery pack and the cells from undesired operating conditions.
To do so, it has some predefined values stored in flash memory to be compared at runtime. These
threshold values are located in the data_flash.h file. They are defined based on the Li-Ion cell
characteristics as shown in Figure 4. The battery pack threshold values are defined accordingly to the cell
threshold values; Figure 5 shows the correlation.
Vsov
Vcov
Vcuv
Battery Short
Circuit
Condition
Precharge
tcuv
Fast Charge
Constant Voltage Mode
tcov
Figure 4. Cell Charging Profile
Voltage, V
Pack End Of Charge Voltage
Full Charge Clear Volts
Pack End Of Discharge Voltage
t3
t1 t2
Note:
t1 – CHARGE_TAPER_TIME
t2 – CC-CV_QUAL_TIME
t3 – END_OF_DISCHARGE_QUAL_TIME
Capacity, Ah
Figure 5. Battery Pack Threshold Values
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
7
Software
2.1.2
www.ti.com
Cell Balancing
A common problem of multi-cell battery packs is cell imbalance. Cell imbalance is a detriment to the
runtime and life span of the whole battery system. To solve this problem, cells with similar state of charge
level (SOC) are usually arranged together.[6] However, an imbalance in the state of charge may develop
between cells and reduce the overall capacity of the pack. Cell balancing is method that minimizes this
problem by equalizing the cells, allowing the battery pack to operate longer.[7]
A difference in cell voltages is the most common manifestation of unbalance, which can be corrected
either instantaneously or gradually through bypassing cells with higher voltage. This application report
describes a simple method of passive cell balancing based on the differences between the cell voltages. If
the difference exceeds the predefined threshold (defined in file data_flash.h), bypass is activated.[8]
This algorithm is active only when the battery pack is in charging mode. It can simultaneously perform
multi-cell balancing by determining which cells have to be bypassed based on the voltage difference
between the cell with the highest voltage (in the whole pack) and the voltage existing on the cell to be
balanced. Figure 6 shows the cell balancing flowchart.
CellBalancing
True
Is Cell Balancing Active?
False
Has the Max Balancing Timer Expired?
True
End
False
Go to SOV mode
Pack is now in SOV mode
Has the Cell Balancing Timer Expired?
False
Is the Battery Pack in Charge Mode?
True
False
True
Are there any imbalanced cells?
False
True
Are the unbalanced cells voltages
higher than the balancing threshold ?
False
Stop cell balancing timers
Reset all cell balancing timers
Disable all bypass resistors
True
Is the cell voltage higher than CUV threshold?
False
True
Start cell balancing timer
Reset cell balancing timers
Find Imbalanced cells on each BQ76PL536 device
Enable bypass resistors of the cells with higher
voltages than the balancing threshold
Reset balancing timer and continue balancing
End
Figure 6. Cell Balancing Flowchart
8
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
Software
www.ti.com
2.1.3
Communication Ports
The battery management system is capable of reporting the battery pack status by sending data to a host
or charger using USB or asynchronous serial protocol (UART). To select any of these communication
methods, the user must define it in the main.h file.
The USB module on the MSP430 MCU is configured to act as a USB-CDC device. For more information
on the API functions and the structure of the USB stack, see the Programmer's Guide: MSP430 USB API
Stack for CDC/HID.[9]
The UART API functions are defined in the UART.h, UART.c, and TI_UART_Regs.h. For more information
on the specifics of these functions, see INDEX_OPEN_THIS_FILE.html in the folder located in the folder
that contains this application report software …/MSP430_BMS_BQ76PL536/docs.
The valid commands accepted by the communication ports are:
"ch" letters + Car Return key sets the battery management system in charge mode
"di" letters + Car Return Key sets the battery management system in discharge mode
"p" letter + Car Return key shows the battery pack status
"c" letter + Car Return Key shows the specific BQ76PL536 device status and cell voltages, entering
this command multiple times cycles through the stacked BQ76PL536 devices.
2.1.3.1
Instructions for Interfacing the USB Device to a Windows PC
For each example, open the IAR/CCE workspace, download the project, and run it. Attach the hardware to
a PC. If this is the first time attaching hardware equipped with the USB CDC API, you'll probably be
prompted for a driver when you attach it. In Windows, direct it to the INF file MSP430_CDC.inf that is
located in the root directory of the API. Note that the driver *.sys files are already in Windows; but an INF
file must be supplied in order for the device to associated with it. When the installation is completed, start
Hyperterminal or another terminal application. Select the appropriate COM port. (After an installation, this
is usually the one with the highest number. If necessary, use the Windows Device Manager to identify
which COM port is associated with the MSP430 MCU.) The baud rate and other COM port configuration
settings do not matter. When working with terminal applications, it will soon be noticed that they weren't
written to be tolerant of the COM port disappearing. Whenever the device program is reset while the port
is open, or if the cable is removed, and then a re-connect is attempted, the terminal application must close
and re-open the port. However, there's an order in which this must be done:
1. Close the terminal's connection to the port.
2. Connect the USB device to the PC; if the PC volume is set to an audible level, an alert can be heard
indicating that a new device has been attached.
3. Re-open the terminal's connection to the port.
In short, the port should not be open while the device enumerates. Once learned, this becomes an easy
habit. This is merely a symptom of using an old software mechanism (COM ports) over a new medium
(USB); terminal applications assume the device is always connected.
NOTE: Sometimes when first attaching the FET tool to the target board, the device can't make a
connection. Remove the JTAG connector and USB cable to remove power from the board
for a few seconds, then re-connect. Usually it is able to make a connection after this
procedure.
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
9
Software
2.2
www.ti.com
File Structure
Table 7 shows a list describing the contents of each file used in this application report software. For more
information on the specifics of these files see INDEX_OPEN_THIS_FILE.html in the folder that contains
this application report software /MSP430_BMS_BQ76PL536/docs.
Table 7. Battery Management System Software Files
File
Description
bq_pack.c [code]
This file contains all of the functions of the BQ76PL536 devices
bq_pack.h [code]
This file contains all the definitions of the BQ76PL536 devices
data_flash.c [code]
This file contains all the functions needed to access to the battery pack information stored in the
MSP430 MCU flash memory
data_flash.h [code]
This file contains all the definitions of the battery pack
defMSP430USB.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
descriptors.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
descriptors.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
dma.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
hal_macros.h [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
hal_pmm.c [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
hal_pmm.h [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
hal_UCS.c [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
hal_UCS.h [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
main.c [code]
This file contains the state machine functions and the console functions, It also contains the
application functions and interrupt service routines
main.h [code]
This file contains all the definitions of the functions declared in main.c. It also contains the global
variables used in other modules
spi_if.c [code]
This file contains the SPI functions and the CRC calculation
spi_if.h [code]
This file contains the SPI functions
TI_IO_Regs.h [code]
Generic I/O ports register definition
TI_USCI_SPI_Regs.h [code]
Provides definitions for the SPI Hardware abstraction layer (HAL)
TI_USCI_UART_Regs.h [code] Generic UART register definition
10
TLV.c [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
TLV_descriptors.h [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
types.h [code]
This file contains definitions for the Hardware Abstraction Layer (HAL) created for the MSP430
MCU
UART.c [code]
This file contains all the required functions to send and receive data using the UART module
UART.h [code]
This file contains all the required functions to send and receive data using the UART module
usb.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
usb.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
usb_eventHandling.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
UsbCdc.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
References
www.ti.com
Table 7. Battery Management System Software Files (continued)
File
3
Description
UsbCdc.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
USBCDC_constructs.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
USBCDC_constructs.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
UsbIsr.c [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
UsbIsr.h [code]
For more information on this file, see Programmers Guide: MSP430 USB API Stack for CDC/HID
(available in SLAC285)
References
1.
2.
3.
4.
5.
6.
7.
MSP430F552x data sheet (SLAS590)
bq76PL536 data sheet (SLUSA08)
BQ76PL536 EVM Quick Start Guide (SLUU437)
MSP430™ Hardware Tools User's Guide (SLAU278)
MSP430x5xx/MSP430x6xx Family User's Guide (SLAU208)
"Cell balancing buys extra run time and battery life" By Sihua Wen, Texas Instrument Inc. (SLYT322)
"Battery Cell Balancing: What to Balance and How" By Yevgen Barsukov, Texas Instruments Inc.
(http://focus.ti.com/download/trng/docs/seminar/Topic%202%20%20Battery%20Cell%20Balancing%20-%20What%20to%20Balance%20and%20How.pdf)
8. Cell Balancing With the bq77PL900 (SLUA463)
9. Programmer's Guide: MSP430™ USB API Stack for CDC/HID (available in SLAC285)
SLAA478 – December 2010
Submit Documentation Feedback
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
11
www.ti.com
Appendix A Benefits of the Ultra-Low-Power MSP430-Based Solution
This appendix describes the benefits and power considerations of using the MSP430 microcontrollers in
this multi-cell Li-Ion battery management system.
A.1
Power Modes
This application can run in three power modes. Table 8 through Table 10 show the multiple power
schemes and the supply current on each scheme:
• Active Mode
In this mode, the battery management system is reading the status of the cells and sampling the
voltages present at the cells. The BQ76PL536 devices and the MSP430F5529 are in active mode
during 25 ms when not sending data to the host; when the battery management system is exchanging
information with the host, then the system is active during 100 ms.
Table 8. Supply Currents in Active Mode
•
Device
Supply Current
Typical (mA)
Supply Current
Maximum (mA)
BQ76PL536
10.5
15
MSP430F5529
10.1
11
Low-Power Mode
In this mode, the BQ76PL536 devices are in protect mode, and the MSP430F5529 is in low-power
mode 0. Table 9 shows the supply currents.
Table 9. Supply Currents in Low-Power Mode
Supply Current
(µA)
Device
(1)
(2)
•
(1)
Supply Current
Maximum (1) (µA)
BQ76PL536
45
60
MSP430F5529
83 (2)
92 (2)
These currents were measured at 25°C. See the device-specific data
sheet for more information.
MSP430F5529 is in low-power mode 3 crystal mode. See the
device-specific data sheet for more information
Ultra-Low-Power Mode
In this mode, the BQ76PL536 devices are in protect mode and the MSP430F5529 is in low-power
mode 3. Table 10 shows the supply currents. Note that USB cannot be used in this mode.
Table 10. Supply Currents in Ultra-Low-Power Mode
Supply Current
(µA)
Device
(1)
(2)
12
(1)
Supply Current
Maximum (1) (µA)
BQ76PL536
45
60
MSP430F5529
2.5 (2)
3.9 (2)
These currents were measured at 25°C. See the device-specific data
sheet for more information.
MSP430F5529 is in low-power mode 3 crystal mode. See the
device-specific data sheet for more information
Multi-Cell Li-Ion Battery Management System Using MSP430F5529 and
bq76PL536
© 2010, Texas Instruments Incorporated
SLAA478 – December 2010
Submit Documentation Feedback
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are
sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard
warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where
mandated by government requirements, testing of all parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,
or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a
warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual
property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied
by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive
business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional
restrictions.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all
express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not
responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably
be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing
such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products
and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be
provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in
such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at
the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are
designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated
products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DLP® Products
www.dlp.com
Communications and
Telecom
www.ti.com/communications
DSP
dsp.ti.com
Computers and
Peripherals
www.ti.com/computers
Clocks and Timers
www.ti.com/clocks
Consumer Electronics
www.ti.com/consumer-apps
Interface
interface.ti.com
Energy
www.ti.com/energy
Logic
logic.ti.com
Industrial
www.ti.com/industrial
Power Mgmt
power.ti.com
Medical
www.ti.com/medical
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
RFID
www.ti-rfid.com
Space, Avionics &
Defense
www.ti.com/space-avionics-defense
RF/IF and ZigBee® Solutions www.ti.com/lprf
Video and Imaging
www.ti.com/video
Wireless
www.ti.com/wireless-apps
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2010, Texas Instruments Incorporated